Solve: $\dfrac{5}{4} - \dfrac{1}{3} - \dfrac{1}{2} = $
Let's look at the multiples of each denominator and see which multiples they have in common. Denominator Multiples ${4}$ $4, 8, \underline{{12}}, 16$ ${3}$ $3, 6, 9, \underline{{12}}, 15$ ${2}$ $2, 4, 6, 8, 10, \underline{{12}}$ The least common multiple is ${12}$. Let's use multiplication to make each fraction have a denominator of $12$. $\begin{aligned} &{\dfrac{5}{4}}=\dfrac{{5} \times 3}{{4} \times3} = {\dfrac{15}{12}}\\\\ &{\dfrac{1}{3}}=\dfrac{{1} \times 4}{{3} \times4} = {\dfrac{4}{12}}\\\\ &{\dfrac{1}{2}}=\dfrac{{1} \times 6}{{2} \times6} = {\dfrac{6}{12}} \end{aligned}$ $\begin{aligned} &{\dfrac{5}{4}} - {\dfrac{1}{3}} - {\dfrac{1}{2}}\\\\ =& {\dfrac{15}{12}} - {\dfrac{4}{12}} - {\dfrac{6}{12}}\\\\ =&\dfrac{{15} - {4} - {6}}{12}\\\\ =&\dfrac{11-{6}}{12}\\\\ =&\dfrac5{12} \end{aligned}$ ${\dfrac{5}{4}} - {\dfrac{1}{3}} - {\dfrac{1}{2}} = \dfrac{5}{12}$